title: Two pimarane diterpenoids from Ephemerantha lonchophylla and their evaluation as modulators of the multidrug resistance phenotype.
abstract: Two new pimarane diterpenoids, lonchophylloids A (1) and B (2), were isolated from the stems of Ephemerantha lonchophylla. The structures of 1 and 2 were established predominantly through the application of extensive 1H-and 13C-NMR, 1D- and 2D-homonuclear and heteronuclear correlation NMR experiments, and X-ray diffraction methods. Consistent with structure--activity predictions, both compounds were capable of sensitizing cells that expressed the multidrug resistance phenotype to the toxicity of the anticancer drug doxorubicin.
authors.affiliation: Institute of Traditional Chinese Medicine and Pharmacology, Nanjing University of Traditional Chinese Medicine, People's Republic of China. gma@gamma.is.tuc.edu
authors.forename: G X
authors.initials: GX
authors.lastname: Na
authors.forename: T S
authors.initials: TS
authors.lastname: Wang
authors.forename: L
authors.initials: L
authors.lastname: Yin
authors.forename: Y
authors.initials: Y
authors.lastname: Pan
authors.forename: Y L
authors.initials: YL
authors.lastname: Guo
authors.forename: G A
authors.initials: GA
authors.lastname: LeBlanc
authors.forename: M G
authors.initials: MG
authors.lastname: Reinecke
authors.forename: W H
authors.initials: WH
authors.lastname: Watson
authors.forename: M
authors.initials: M
authors.lastname: Krawiec
mesh_terms: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000096:biosynthesis; D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification* / Q000494:pharmacology; D004317:Doxorubicin / Q000494:pharmacology; D019450:Genes, MDR / Q000187:drug effects*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D051379:Mice; D010616:Phenanthrenes / Q000302:isolation & purification* / Q000494:pharmacology; D010641:Phenotype; D018547:Plant Stems / Q000737:chemistry; D013329:Structure-Activity Relationship; D014407:Tumor Cells, Cultured; D014961:X-Ray Diffraction
chemical_list: D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000972:Antineoplastic Agents, Phytogenic; D010616:Phenanthrenes; C110799:lonchophylloid A; C110800:lonchophylloid B; D004317:Doxorubicin